iOS开发-Reachability实时检测Wifi,2G/3G/4G/网络状态
最近遇到一个功能就是根据用户当前的网络状，用户未联网需要提示一下，如果是Wifi可以推荐一些图片新闻，如果是3G模式设置为无图的模式，获取网络状态比较简单，毕竟中国现在的流量还是一个比较贵的状态，哪天用户发现App消耗流量过多说不定就干掉了App。不过苹果的Reachability都解决了以上问题，使用起来也比较方便，具体的稍微简单分析一下。 Reachability.h头文件代码: + View Code Reachability.m文件: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 #import <arpa/inet.h> #import <ifaddrs.h> #import <netdb.h> #import <sys/socket.h> #import <CoreFoundation/CoreFoundation.h> #import "Reachability.h" NSString *kReachabilityChangedNotification = @ "kNetworkReachabilityChangedNotification" ; #pragma mark - Supporting functions #define kShouldPrintReachabilityFlags 1 static void PrintReachabilityFlags(SCNetworkReachabilityFlags flags, const char * comment) { #if kShouldPrintReachabilityFlags NSLog (@ "Reachability Flag Status: %c%c %c%c%c%c%c%c%c %s\n" , //当前网络2G/3G/4G蜂窝网络 (flags & kSCNetworkReachabilityFlagsIsWWAN) ? 'W' : '-' , //网络是否可达 (flags & kSCNetworkReachabilityFlagsReachable) ? 'R' : '-' , (flags & kSCNetworkReachabilityFlagsTransientConnection) ? 't' : '-' , (flags & kSCNetworkReachabilityFlagsConnectionRequired) ? 'c' : '-' , (flags & kSCNetworkReachabilityFlagsConnectionOnTraffic) ? 'C' : '-' , (flags & kSCNetworkReachabilityFlagsInterventionRequired) ? 'i' : '-' , (flags & kSCNetworkReachabilityFlagsConnectionOnDemand) ? 'D' : '-' , (flags & kSCNetworkReachabilityFlagsIsLocalAddress) ? 'l' : '-' , (flags & kSCNetworkReachabilityFlagsIsDirect) ? 'd' : '-' , comment ); #endif } static void ReachabilityCallback(SCNetworkReachabilityRef target, SCNetworkReachabilityFlags flags, void * info) { #pragma unused (target, flags) NSCAssert (info != NULL , @ "info was NULL in ReachabilityCallback" ); NSCAssert ([(__bridge NSObject *) info isKindOfClass: [Reachability class ]], @ "info was wrong class in ReachabilityCallback" ); //http://www.cnblogs.com/xiaofeixiang Reachability* noteObject = (__bridge Reachability *)info; // Post a notification to notify the client that the network reachability changed. [[ NSNotificationCenter defaultCenter] postNotificationName: kReachabilityChangedNotification object: noteObject]; } #pragma mark - Reachability implementation @implementation Reachability { BOOL _alwaysReturnLocalWiFiStatus; //default is NO SCNetworkReachabilityRef _reachabilityRef; } //通过域名进行实例化 博客园-Fly_Elephant + (instancetype)reachabilityWithHostName:( NSString *)hostName { Reachability* returnValue = NULL ; SCNetworkReachabilityRef reachability = SCNetworkReachabilityCreateWithName( NULL , [hostName UTF8String]); if (reachability != NULL ) { returnValue= [[ self alloc] init]; if (returnValue != NULL ) { returnValue->_reachabilityRef = reachability; returnValue->_alwaysReturnLocalWiFiStatus = NO ; } } return returnValue; } //通过ip地址实例化Reachability + (instancetype)reachabilityWithAddress:( const struct sockaddr_in *)hostAddress { SCNetworkReachabilityRef reachability = SCNetworkReachabilityCreateWithAddress(kCFAllocatorDefault, ( const struct sockaddr *)hostAddress); Reachability* returnValue = NULL ; if (reachability != NULL ) { returnValue = [[ self alloc] init]; if (returnValue != NULL ) { returnValue->_reachabilityRef = reachability; returnValue->_alwaysReturnLocalWiFiStatus = NO ; } } return returnValue; } //检测是否能够直接连上互联网 + (instancetype)reachabilityForInternetConnection { struct sockaddr_in zeroAddress; bzero(&zeroAddress, sizeof (zeroAddress)); zeroAddress.sin_len = sizeof (zeroAddress); zeroAddress.sin_family = AF_INET; return [ self reachabilityWithAddress:&zeroAddress]; } //检测当前网络是否能够联上wifi + (instancetype)reachabilityForLocalWiFi { struct sockaddr_in localWifiAddress; bzero(&localWifiAddress, sizeof (localWifiAddress)); localWifiAddress.sin_len = sizeof (localWifiAddress); localWifiAddress.sin_family = AF_INET; // IN_LINKLOCALNETNUM is defined in <netinet/in.h> as 169.254.0.0. localWifiAddress.sin_addr.s_addr = htonl(IN_LINKLOCALNETNUM); Reachability* returnValue = [ self reachabilityWithAddress: &localWifiAddress]; if (returnValue != NULL ) { returnValue->_alwaysReturnLocalWiFiStatus = YES ; } return returnValue; } #pragma mark - Start and stop notifier - ( BOOL )startNotifier { BOOL returnValue = NO ; SCNetworkReachabilityContext context = {0, (__bridge void *)( self ), NULL , NULL , NULL }; //SCNetworkReachabilitySetCallback函数为指定一个target //当设备对于这个target链接状态发生改变时(比如断开链接，或者重新连上)，则回调reachabilityCallback函数， if (SCNetworkReachabilitySetCallback(_reachabilityRef, ReachabilityCallback, &context)) { if (SCNetworkReachabilityScheduleWithRunLoop(_reachabilityRef, CFRunLoopGetCurrent(), kCFRunLoopDefaultMode)) { returnValue = YES ; } } return returnValue; } - ( void )stopNotifier { if (_reachabilityRef != NULL ) { SCNetworkReachabilityUnscheduleFromRunLoop(_reachabilityRef, CFRunLoopGetCurrent(), kCFRunLoopDefaultMode); } } - ( void )dealloc { [ self stopNotifier]; if (_reachabilityRef != NULL ) { CFRelease(_reachabilityRef); } } #pragma mark - Network Flag Handling - (NetworkStatus)localWiFiStatusForFlags:(SCNetworkReachabilityFlags)flags { PrintReachabilityFlags(flags, "localWiFiStatusForFlags" ); NetworkStatus returnValue = NotReachable; if ((flags & kSCNetworkReachabilityFlagsReachable) && (flags & kSCNetworkReachabilityFlagsIsDirect)) { returnValue = ReachableViaWiFi; } return returnValue; } - (NetworkStatus)networkStatusForFlags:(SCNetworkReachabilityFlags)flags { PrintReachabilityFlags(flags, "networkStatusForFlags" ); if ((flags & kSCNetworkReachabilityFlagsReachable) == 0) { // The target host is not reachable. return NotReachable; } NetworkStatus returnValue = NotReachable; if ((flags & kSCNetworkReachabilityFlagsConnectionRequired) == 0) { /* If the target host is reachable and no connection is required then we'll assume (for now) that you're on Wi-Fi... */ returnValue = ReachableViaWiFi; } if ((((flags & kSCNetworkReachabilityFlagsConnectionOnDemand ) != 0) || (flags & kSCNetworkReachabilityFlagsConnectionOnTraffic) != 0)) { /* ... and the connection is on-demand (or on-traffic) if the calling application is using the CFSocketStream or higher APIs... */ if ((flags & kSCNetworkReachabilityFlagsInterventionRequired) == 0) { /* ... and no [user] intervention is needed... */ returnValue = ReachableViaWiFi; } } if ((flags & kSCNetworkReachabilityFlagsIsWWAN) == kSCNetworkReachabilityFlagsIsWWAN) { /* ... but WWAN connections are OK if the calling application is using the CFNetwork APIs. */ returnValue = ReachableViaWWAN; } return returnValue; } - ( BOOL )connectionRequired { NSAssert (_reachabilityRef != NULL , @ "connectionRequired called with NULL reachabilityRef" ); SCNetworkReachabilityFlags flags; if (SCNetworkReachabilityGetFlags(_reachabilityRef, &flags)) { return (flags & kSCNetworkReachabilityFlagsConnectionRequired); } return NO ; } //获取当前网络状态 - (NetworkStatus)currentReachabilityStatus { NSAssert (_reachabilityRef != NULL , @ "currentNetworkStatus called with NULL SCNetworkReachabilityRef" ); NetworkStatus returnValue = NotReachable; SCNetworkReachabilityFlags flags; if (SCNetworkReachabilityGetFlags(_reachabilityRef, &flags)) { if (_alwaysReturnLocalWiFiStatus) { returnValue = [ self localWiFiStatusForFlags:flags]; } else { returnValue = [ self networkStatusForFlags:flags]; } } return returnValue; } @end AppDelegate中的实现: 1 2 3 4 5 6 7 8 9 10 - ( BOOL )application:(UIApplication *)application didFinishLaunchingWithOptions:( NSDictionary *)launchOptions { //添加一个系统通知 [[ NSNotificationCenter defaultCenter] addObserver: self selector: @selector (reachabilityChanged:) name:kReachabilityChangedNotification object: nil ]; //初始化 self .internetReachability=[Reachability reachabilityForInternetConnection]; //通知添加到Run Loop [ self .internetReachability startNotifier]; [ self updateInterfaceWithReachability:_internetReachability]; return YES ; } 回调函数: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 - ( void ) reachabilityChanged:( NSNotification *)note { Reachability* curReach = [note object]; NSParameterAssert ([curReach isKindOfClass:[Reachability class ]]); [ self updateInterfaceWithReachability:curReach]; } - ( void )updateInterfaceWithReachability:(Reachability *)reachability { NetworkStatus netStatus = [reachability currentReachabilityStatus]; switch (netStatus) { case NotReachable: NSLog (@ "====当前网络状态不可达=======http://www.cnblogs.com/xiaofeixiang" ); break ; case ReachableViaWiFi: NSLog (@ "====当前网络状态为Wifi=======博客园-Fly_Elephant" ); break ; case ReachableViaWWAN: NSLog (@ "====当前网络状态为3G=======keso" ); break ; } } 模式测试 Wifi模式-wuWifi-连接Wifi，显示结果如下: 如果直接通过host实例化也可以: 1 2 NSString *remoteHostName = @ "www.cnblogs.com/xiaofeixiang" ; self .hostReachability = [Reachability reachabilityWithHostName:remoteHostName]; 本文转自Fly_Elephant博客园博客，原文链接：http://www.cnblogs.com/xiaofeixiang/p/4472343.html，如需转载请自行联系原作者
